This invention relates generally to differential communication protocols methods and apparatus, and more particularly to methods and apparatus that provide automatic bus monitoring and management.
Common differential communication protocols, such as RS-485 and CAN (Controller Area Network), require various serial and parallel termination resistances to ensure robust operation. When this resistance is incorrect, erratic system behavior can occur that can be very difficult to diagnose and fix.
It is known to measure termination resistance using a hand-held digital voltmeter, but this requires a powered-down system and human interaction. Thus, there is a long felt need for something that enables a system to report termination status automatically and remotely, and to operate intelligently in degraded modes, when applicable.